Degradation estimation method for high voltage battery

Abstract

A degradation estimation method system of a high voltage battery is provided that detect degradation of a battery. The degradation estimation method includes obtaining, by a controller, information about an input voltage, an input current and an external temperature of a slow charger. The controller is configured to calculate an output power used for charging the battery, based on an input power calculated based on the input voltage and the input current. In addition, the method includes calculating, by the controller, a mean charging current based on the output power and the battery charging voltage and calculating a battery degradation degree based on the mean charging current.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims under 35 U.S.C. §119(a) the benefit of Korean Patent Application No. 10-2013-0100059 filed Aug. 23, 2013, the entire contents of which are incorporated herein by reference.BACKGROUND[0002](a) Technical Field[0003]The present disclosure relates to a method and system for accurately estimating degradation of a high voltage battery within an electric vehicle more accurately, a plug-in hybrid electric vehicle or the like.[0004](b) Background Art[0005]Generally, a high voltage battery is loaded within an electric vehicle (EV), a plug-in hybrid electric vehicle (PHEV) or the like to store electric energy used as a driving force of the vehicles. When the high voltage battery is used continuously in succession, a degradation phenomenon occurs, thus decreasing the capacity of the battery. When degradation occurs, the accuracy of State Of Charge (SOC) also deteriorates, thereby reducing gas mileage per SOC, deterioration of p...

AI Technical Summary

Benefits of technology

[0019]3. It may be possible to improve accuracy of actual SOC and ensure a more stable running state of a vehicle since degradation of a high voltage battery loaded in an EV, a PHEV or the like may be estimated more accurately.

Problems solved by technology

When the high voltage battery is used continuously in succession, a degradation phenomenon occurs, thus decreasing the capacity of the battery.

When degradation occurs, the accuracy of State Of Charge (SOC) also deteriorates, thereby reducing gas mileage per SOC, deterioration of power for acceleration, or the like.

Since a sensed charging current value is used, a measurement error of a current sensor may be applied, influencing the final degradation degree calculation result.

In other words, since a value measured by a sensor is used as a current value for detecting degradation of a high voltage battery in the known technique, an error of the current sensor is applied as an error of the degradation degree.

Therefore, when the sensor error increases, the calculated degradation degree also has an increased error.

Therefore, in the known technique, degradation may be detected in the power source having predetermined specifications.

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